There's only one thing worse than a technological breakthrough that never gets going: one that makes a promising start, but fails to fulfil its potential. We can live with promised advancements of technologies like speech recognition – a theoretical godsend which would make the lives of RSI suffers easier if only it worked.

With 64-bit computing, however, the frustration is more pronounced. We should have faster and frankly better computers by now, but for all its much vaunted advantages, 64-bit still isn't mainstream. The situation is made all the more annoying because the pieces of the puzzle began falling into place over seven years ago, when Windows XP 64-bit was released.

The hardware's there too: both Intel and AMD have long offered 64-bit processors. Yet driver incompatibilities and a lack of updated software have stalled progress in 64-bit computing. Thankfully, that's all about to change. Microsoft Windows Server 2008 will be the last version of the OS to be released in both 32-and 64-bit flavours.

Major companies such as Autodesk and Adobe have also put their shoulders behind 64-bit, releasing updated versions of their flagship apps. Finally, laptop makers such as Dell and Lenovo now ship a 64-bit OS almost as often as a 32-bit OS. So after a number of false dawns, is the fire of the 64-bit revolution now being lit?

In theory and practice

Why is 64-bit computing important? The answer is simple: a 32-bit operating system can only access up to 4GB of RAM, whereas a 64-bit OS can access more RAM than anyone could conceivably fit into their PC case: 17.2 million terabytes (TB). In practical terms, a 64-bit Dell workstation such as the Precision T3400 can be configured with 16GB or more of RAM. The difference is profound.

Here's a good visual picture of why the higher memory addressing is important: if the memory size for a 32-bit PC is as big as a standard water pipe to a suburban home, the pipe for a 64-bit computer is as big as the Atlantic Ocean. That's a lot of room for programmers to be innovative in how they handle data, and they wouldn't have to worry about performance or bottleneck issues.

There's another angle to this, however. A 32-bit application can only use 3GB of data for a single process. This means that for many fields – such as the oil and gas industry, or high-end media creation and music production – there is a severe limitation.

Companies such as Pixar and LucasArts have used 64-bit Linux computers for the past decade because they need to work with products like Autodesk's Maya, an app for creating 3D models. On a 32-bit PC running Windows, the 3GB limitation per process would mean breaking the models into separate pieces and continually swapping memory to hard disk.